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hush: rename last_waitpid_was_0 to we_have_children

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2009-05-26 14:34:10 +02:00
parent 140def848c
commit e2df5f46d0
1 changed files with 22 additions and 14 deletions
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36
shell/hush.c
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@ -495,7 +495,7 @@ struct globals {
#if ENABLE_HUSH_FAST
unsigned count_SIGCHLD;
unsigned handled_SIGCHLD;
smallint last_waitpid_was_0;
smallint we_have_children;
#endif
/* which signals have non-DFL handler (even with no traps set)? */
unsigned non_DFL_mask;
@ -3292,22 +3292,30 @@ static int checkjobs(struct pipe* fg_pipe)
debug_printf_jobs("checkjobs %p\n", fg_pipe);
errno = 0;
#if ENABLE_HUSH_FAST
if (G.handled_SIGCHLD == G.count_SIGCHLD) {
//bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d was 0?:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.last_waitpid_was_0);
/* avoid doing syscall, nothing there anyway */
if (G.last_waitpid_was_0)
return 0;
errno = ECHILD;
return -1;
}
#endif
attributes = WUNTRACED;
if (fg_pipe == NULL)
attributes |= WNOHANG;
errno = 0;
#if ENABLE_HUSH_FAST
if (G.handled_SIGCHLD == G.count_SIGCHLD) {
//bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p",
//getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe);
/* There was heither fork nor SIGCHLD since last waitpid */
/* Avoid doing syscall, nothing there anyway */
if (!G.we_have_children) {
errno = ECHILD;
return -1;
}
if (fg_pipe == NULL) { /* is WNOHANG set? */
/* We have children, but they did not exit
* or stop yet (we saw no SIGCHLD) */
return 0;
}
/* else: !WNOHANG, waitpid will block, can't short-circuit */
}
#endif
/* Do we do this right?
* bash-3.00# sleep 20 | false
* <ctrl-Z pressed>
@ -3330,7 +3338,7 @@ static int checkjobs(struct pipe* fg_pipe)
bb_perror_msg("waitpid");
#if ENABLE_HUSH_FAST
else { /* Until next SIGCHLD, waitpid's are useless */
G.last_waitpid_was_0 = (childpid == 0);
G.we_have_children = (childpid == 0);
G.handled_SIGCHLD = i;
//bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
}